Telephone-switch.



V. E. GREEN.

TELEPHON SWITCH.

APPLICATION FILED AUG. 6, 1907.

. 9 576 I Patented Sept.,15, 1908.

2 SHEETS-SHEET 1.

v. E. GREEN. TELEPHONE SWITCH.

APPLIGATIUN TILED AUG. 6, 1907.

Patented Sept. 15, 1908.

2 SHEETS-SHEET 2.

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VERNE E. GREEN, OF GALVA, ILLINOIS.

TELEPHONE-SWITCH.

Specification of Letters Patent.

Patented Sept. 15, 1908.

Application filed August 6, 1907. Serial No. 387,354.

To all whom it may concern:

Be it known that I, VERNE E. GREEN, citizen of the United States, residing at Galva, in the county of Henry and State of Illinois, have invented certain new and useful Improvements in Telephone-Switches, of which the following is a specification.

The present invention appertains to a switch designed most especially for use in connection with telephone systems of the nature enabling parties to call one another without the intervention of central or exchange. i

In systems aflording telephonic communication of the type aforesaid, it frequently happens that two or more branch lines come close together at some point and a party resident near such point may advantageously use the present switch so as to avoid delay and veXation should one or more branches be in use, thereby permitting his calling another p arty whose branch is not in use, but the present invention enables such party to cut off the branch lines in use without interrupting communication between the parties talking, while at the same time afiording opportunity for calling any other branch of the system that may not be in use.

The switch cannot be economically and advantageously used in systems requiring a central or exchange, but is designed for party lines in which the subscribers can call one another between themselves, as in rural districts and s arsely settled country.

For a full understanding of the invention and the merits thereof and also to acquire a knowledge of the details of construction and the means for eifecting the result, reference is to be had to the following description and accompanying drawings.

WVhile the invention may be adapted to different forms and conditions by changes in the structure and minor details without departing from the spirit or essential features thereof, still the preferred embodiment is shown in the accompanying drawings, in which:

Figure 1 is a front view of a switch embodying the invention. Fig. 2 is a sectional view on the line :rm of Fig. 1, looking downward. Fig. 3 is a sectional view on the line acw of Fig. 1, looking upward or in the opposits direction. Fig. 4 is a section on the ine y' z of Fig. 1. Fig. 5 is a front view of a modification, showing a switch adapted for lines which are grounded.

Corresponding and like parts are referred to in the following description and indicated in all the views of the drawings by the same reference characters.

The operating parts of the switch are attached to or mounted upon a support 1 of dielectric material and the same may be transparent or opaque according to the nature of the material selected. If the working parts of the switch are to be under observation, the support 1 is preferably of glass. A space is formed in the rear of the support 1 to accommodate the working parts and ordinarily a base or back 2 is provided and is spaced from the support 1, said space being closed at its edges to exclude dust and to prevent tampering with the working parts.

A pair of contact plates 3 and 4 are ar ranged transversely of the support and are connected thereto. Other contact plates 5 and 6 have a similar arrangement and are connected to the support 1, but are differently positioned with reference to the contact plates 3 and 4, so as to prevent interference. The contact plates 3 and 4 touch or are arranged close to the support, whereas the contact plates 5 and 6 are spaced some distance from the support 1. Pairs of spring blades 7 and 8 are arranged to cross the contact plates 3, 4, 5 and 6 about at a right angle and are secured at one end only to the support 1, their opposite ends being free to play between the pairs of contact plates 34 and 5-6. The spring blades 7 and 8 are the movable switch members and are normally in electrical contact with the plates 3 and 4 and form extensions of the several branch lines a, b, c and (Z. The blades 7 are electrically insulated from the plate 3 and normally are in electrical connection with the plate 4. The blades 8 are normally in electrical connection with the plate 3 and electrically insulated from the plate 4. The several branch lines, four being indicated, have their wires electrically connected by leads with the switch and blades 7 and 8 of the respective pairs. The telephone 9 at the point provided with the switch, has its leads connected with the plates 3 and 4, hence is in communication with the several branch lines, as will be readily understood. The plates 5 and 6 serve simply to electrically connect two or more parties that may be talking, thereby leaving the owner of the switch free to call 011 any other branch without interrupting the branch lines that are in use. An extension bell 10 is electrically conany suitable dielectric material may be employed and applied to either the blades or the plates and by preference said material is set V into recesses in the parts to come flush with the surface thereof.

Push buttons are provided for the several pairs of spring switch blades 7 and 8 and each 'push button consists of a head 1 1 and a stem 12, the latter operating through an opening in the support 1, whereas the head 11 overlaps end portions of a pair of blades 7 and 8 so as to simultaneously move the same away from the plates 3 and 4 and into contact with the plates 5 and 6, as when cutting out a branch line to admit of the owner of the switch establishing communication with any other branch of the system not in use. The switch blades 7 and 8 normally bear against the plates 3 and 4 and upon exerting pressure upon any push button, the branch line corresponding to the switch blades controlled by said push button, is electrically disconnected from the plates 3 and 4 and electrically connected with the plates 5 and 6.

Under normal conditions, the owner of the switch is in electrical connection with each subscriber of the party line. 'Suppose a should call I) and while the branch lines 66 and b are in service, the party owning and controlling the switch should desire .to call 0. The party after ascertaining that the branch lines a and b are in use, depresses the push buttons controlling the switch blades 7 and 8 of such lines, thereby connecting the branch lines a and b with each other through the plates 5 and 6, thereby enabling the party 0 to be called and communication established without interrrupting a and b. When pressure is removed from the push buttons controlling the switch blades of the branch lines a and b, the respective switch blades thereof move away from the plates 5 and 6 and into contact with the plates 3 and 4, thereby restoring the party line system to normal condition. The switch may be used to locate trouble in the event of one or more of the branch lines getting out of order, since the party controlling the switch may test each of the branch linesin succession and thereby determine which is out of order.

In the construction shown in Fig. 5, the switch blades 13 are single, since the branch lines are grounded. The plates 14 and 15 are also single and are arranged upon opposite sides of the switch blades 13, the latter normally being in electrical connection with the plate 14 and adapted to make electrical connection with the plate 15 when moved by the application of pressure upon the push buttons 16. The telephone 9 is connected with the plate 14 and is grounded at 17. The eX- tension bell 10 is connected with the plate 15 and is grounded at 17. The operation of the switch is precisely the same as that heretofore described. Two or more parties may be connected electrically through the plate 15 and the respective switch blades 13, thereby leaving the party desiring to use the line free to call and establish communication with any other branch in the system not using the line.

Having thus described the invention, what is claimed as new is:

1. In a switch of the character specified, the combination of a pair of contact plates, pairs of switch blades having one blade of the respective pairs in electrical connection with one of said plates and electrically insulated from the other plate, and having the other switch blade electrically insulated from the first mentioned plate and electrically connected with the other plate, and a second pair of contact plates arranged to electrically connect pairs of switch blades when moved out of contact with the first mentioned pair of plates.

2. A switch of the character specified, comprising a pair of plates 3 and 4, pairs of switch blades having one blade of each pair electrically connected with one of said plates and electrically insulated from the other plate and having the other blade electrically insulated from the plate with which the first mentioned blade is in electrical connection and electrically connected to the other plate, and a second pair of plates 5 and 6 normally out of contact with the switch blades and adapted to electrically connect-the same.

In testimony whereof I ailiX my signature in presence of two witnesses.

VERNE E. GREEN. 

